SYM2POLYS

Improved version of Sym2Polys (by Paul Godfrey).

Description

Sym2Polys (by Paul Godfrey) cannot be run on MATLAB 7(Release 14). This function is an extension of the Matlab SYM2POLY and COEFFS functions in that it allows the coefficients to be symbolic and returns the full coefficient vector including the zero coefficients.

Acknowledgements

The author wishes to acknowledge the following in the creation of this submission:
Sym2Polys

• Required Products: Symbolic Math Toolbox
• MATLAB release: MATLAB 7 (R14)

[udhaya kumar]

There is some problem in the function coeffs which makes this m file a problem for eg if p =s^6+2*s^5+5*s^4+2*s^3+9*s^2+10*s+12 then is returns c =[2 5 2 1 9 10 12] which is wrong

[Mukhtar Ullah]

udhaya kumar,
Thanks for detecting this bug. I have uploaded the bug-fixed version today. It should appear soon in this ML exchange.

[Noviar Ferguson]

It helps me a lot!
Thank you very much!!! =)

[kostas]

Dear Mukhtar,

I was wondering if it is possible to add a new feature to sym2polys.m file, that is to return the coefficients vector (including the zeros) for multivariable polynomials in the format p = a*P1 + b*P1^2 + c*P2 + d*P3^2 + ..., etc

For example, if v is a multivariable (P0001, ..., P0020) monomial v = 64*P0001 + 400*P0010 + 80*P0002 + 336*P0011 + 1218*P0020 + 25*P0003 then with your function sym2polys(v) returns

[ 64, 400*P0010 + 80*P0002 + 336*P0011 + 1218*P0020 + 25*P0003]

instead of

[ 64, 80, 25, 0, 0, 0, 0, 0, 0, 400, 336, 0, 0, 0, 0, 0, 0, 0, 0, 1218]

Please let me know if you can add susch a feature.

Thanks in advance, kostas